A coating composition comprising a cellulose derivative, an epoxidized oil and an amine-aldehyde resin



United States Patent A COATING COMPOSITION COMPRISING A1CEL- LULOSE DERIVATIVE, AN EPQXIDIZED OIL AND AN A'MlNE-ALDEHYDE RESIN -Kehneth R: ConeyyPennsville, Nil, Richer-H B; Pyewaii,

Media, Pat, and Williahi BL Whbllm Pitl'fiaii, NJL', assignors to E. I. du Pgn t t le Nernours and Company, Wilmington, Del., a corporation of Delaware No Drawing. Filed June 6, 195 8, Ser. No. 740,191

5 Cla iln's. (Cl: 260

This application relates to novel coating compositions containing cellulose derivative film-formers and having a very high resistance to attack by; organic solvents and corrosive chemicals as well as improved physicalpr operties. More particularly, this application relates to chemical-resistant cellulose derivative lacquers, especially industrial lacquers, containing-a cured-'epoxidized compound.

Lacquers and similar coating compositions in-which a cellulose derivative, such as nitrocellulose, tliyl' cellulose, cellulose acetate; celluloseacetate btityrate, and the like, is the principal fi1m-f0rmingcomponent have long been known and used in the artl Protective coatings and films formed from such coating compositions have excellent properties in" many respects" an suchcoinpositions have gained wide pread-acce tance in the field for many coating uses. one of th'e principal disadvanrages of such compositions is tlheir relatively poor resistance to attack by organic solvents and corrosivecheniicals. Were it not for this drawback, coating cdrnpositions having cellulose derivative film tor riier'siwould have achieved even wider use than they have to are;

It is a principal object of the present invention to provide novel cellulose derivative coating compositions having improved r'e'sis'tarice to attack by organic solvents and corrosive chemical materials, and havinginiproved physical properties.

it is a further object of the invention to provide such coating compositions which" are economical to man rfacture and convenient touse: Gtherandadditiofi objects of the-invention willbecome appainrriemacm sidcratiorr of theensuing specification and'clainfs.

The foregoing objectives are accomplished byi'ricorpcrating into the cellulose derivative coating composition a suitable portion of ep'oxidize'd triglyceride of soya bean oil or epoxidized acetylated triglyceride of castor oil plus a resinous -urea-formaldehyde,-nielamineformaldehyde, or benzoguanainine formaldehyde' ciiiih'g agent torthe epoxy material.

The epoxidized triglyceride of soya bean oil and epoxidized acetylatecl triglycerideof'castor oilarereadifly available commercial chemicals which are"produced.industrially by the reaction of-hydrogenpero3rideor peracetic acid with unsaturatedfatty acid estersan'd' the oils.

In our coating compositions," the epoxidized material is cured witha urea-formaldehyde melamineformalde hyde, or bandqaanamme-rerntamehyaeresin; a's-will' be more particularly hereinafter described The coating composition may also contain acatalyst for hast'ening the cure; Many of a varietyo f'oth'e'i optional additives 3,003,978 Oct. 10, 1961 M n w t-i Patented Parts'by weight SD-2-B mam] 11.4 To V I u na Xylene 7 Methyl'is'obutyl keton'ei;

Butyl Cellosolve i ,1 GI col butyl ether manufactured by oriibii'c'arhd lcals cmpany.

EXAMPLE I A lacquer was prepared by dissolving the following some; components in the solvent a /21) seafloos'olidsw'eight basis:

v Parts byweight Nitrocellulose (120% nitrogen), type HB 14 E, manufactured by E. I. de Pout de Nemours'and K 'AHIP -r: ..i it a i Admen epoxiclized: triglyceride of soya bean oil manufactured v by the1Archer=Daniels-Midland' Co. (epox ide value' 0.37, molecular Weight approximately 1000) 50 Uformite F-200-E;'-mutanol=modifid urea-formal dehyde resinmanufactufedby' Rohm &"Ha's's"Co z" 50 Dibutyl phthalate t 25 Monobutyl acid orthophosphate. v

. ennui E A lacquer was prepared dissolving the following solidcemp ie its iinrie inventor?:in8o/2cs816eniaosol'i'ds weiglit basis? 7 g I r I Partsb we Nitrocellulose" (12.0% nitrogen), type HB 14*E;

manufactured by E. I: (in Pontde- Nernoursand Co., I .:"100 Admex:219; eporridized triglycerideof 569a Bean'- oil manufactured by the Archer aural-inflamed Co; (epbxide value 0.37, moleculai weight proximately 1000) W 50 718, butano'l modified resin, manufactured by E. I; do" Pent deNemmfiE and Col, ma a '5 Dibtiiyl' plith'nlir'e" 2;

ExAMrrEnt A" nearer was 5 iara" elicitin solid components in the solvent on an 80/20 solventtosolids weight basis:

Parts by weight Nitrocellulose (12.0% nitrogen), type HB 14 E, manufactured by E. I. du Pont de Nemours and Co., Inc "Admeif 710, epoxidized triglyceride of soyabean oil manufactured by the Archer-Daniels-Midland Co. (epoxide value 0.37, molecular weight approximately 1000) 76 Uformite 158, propanol-modified urea-formaldehyde resin, manufactured by Rohm & Haas Company 50 Monobutyl acid orthophosphate S i A EXAMPLEIV A lacquer was prepared by dissolving the following solid components in the solvent on an 80/20 solvent-tosolids weight basis: Parts by weight Nitrocellulose 12.0% nitrogen), type HB 14 E,

' manufactured byE. I. du Pont de Nemours and Co., Inc Estynox 308, epoxide of the acetylatedtriglyceride of castor oil manufactured by the Baker Castor Oil Co. (epoxide value 0.l8l, molecular weight 1,081) 50 "Uformite. 158, propanol-modified urea-formaldehyde resin manufactured by Rohm & Haas Comnany 50 Dibutyl phthalat 26 Monobutyl acid orthophosphate EXAMPLE V I A lacquer was prepared by dissolving the following solid components in the solvent on an 80/20 solvent-tor solids weight basis:

Parts by weight Nitrocellulose 12.0% nitrogen), type HB 14 E,

manufactured by E. I. du Pont de Nemours and Co., In 100 Admex" 710, epoxidized triglyceride of soya bean oil manufactured by the 'Archer-Daniels-Midland Co..(epoxide value 0.37, molecular weight approx- -imately-1000) Z50 Uformite MM55, butanol-modified melamineformaldehyde resin, .manufactured by Rohm & Haas. Company 50 D ty phth la e. 25 Monobutyl acid orthophosphate 5 EXAMPLEVI V i A lacquer was prepared by dissolving the following solid components in the solvent on an 80/20 solvent-tosolids weight basis:

' Parts by weight Nitrocellulose (12.0% nitrogen), type HB 14 E, manufactured by E. I. du Pont de Nemours and Co., In Admex 710, epoxidized triglyceride of soya bean oil manufactured by the Archer-Daniels-Midland Co. (epoxide value 0.37, molecular weight approximately 1000) V 50 Butanol modified benzoguanarnine formaldehyde resin 50 Dibutyl phthalate 25 Monobutyl acid orthophosphate 5 EXAMPLE VII A lacquer was prepared by dissolvingthe following solid components in a solvent on an 80/20 solvent-tosolids weight basis. (The carbon black was dispersed in the lacquer by methods well known to the art):

Parts by weight Nitrocellulose (12.0% nitrogen), type HB 14 E,

manufactured by E. I. du Pont de Nemours and Co., In 100 Admex 710, epoxidized triglyceride of soya bean oil manufactured by the Archer-Daniels-Midland Co. (epoxide value 0.37, molecular weight approximately 1000) Uformite F-200-E, butanol-modified urea-form aldehyde resin, manufactured by Rohm & Haas Company 50 Dibutyl phthalate -c 25 Carbon black (pigment) 11.25 Monobutyl acid orthophosphate 5.0

, EXAMPLE VIII A lacquer was prepared by dissolving the following solid components in a solvent on an 80/20 solvent-tosolids weight basis: Parts by weight Nitrocellulose (12.0% nitrogen), type HB 14 E, manufactured by E. I. du Pont de Nemours and Co., In Admex 710, epoxidized triglyceride of soya bean oil manufactured by the Archer-Daniels-Midland Co. (epoxide value 0.37, molecular weight approximately 1000) RC-718, butanolmodified ureaformaldehyde resin, manufactured by E. I. du Pont de Nemours Monomethyl acid orthophosphate 5 In the lacquer formulations described in Examples I through VIII, the solids components were dissolved and dispersed in the solvent system by conventional and wellknown techniques. When used, the catalyst for curing the epoxidized material with the resin, i.e., a monoalkyl acid orthophosphate or citric acid, is not added simultaneously with the other components but rather is added shortly before the lacquer is to be used.

Examples IX to XVH, which follow, illustrate the in- .vention in connection with cellulose derivative coating compositions other than nitrocellulose lacquers. In all of these examples, the following solvent system was used unless otherwise indicated:

- Parts by weight ,SD-ZB ethanol 11,4 Ioluene 54.3 Methyl ethyl keton 19.6 Butyl Cellosolve 14.7

- 1 Glycol hutyl ether manufactured by Union Carbide Chenil' cals Company.

EXAMPLE IX EXAMPLE X mately 1000) 50 RC-718, butanol-modified v urea-formaldehyde resin manufactured by E. I. du Pont de Nemours V Co., Inc 50 Dibutyl phthalate; 25 Monobutyl acidorthO' hos hate; 5

EXAMPLE XI A lacquer was prepared by dissolving the following solid components in' the solvent on an 80/20 solvent-tosolids weight basis:

. Parts by weight Ethyl cellulose (42.5 4315 ethoikyl, 22 centi poises) 100 Adrnex 710, epoxidized triglyceride of soya bean oil 50 Uformite F-158, propanol-modified urea-formaldehyde resin manufactured by Rohm & Haas Company 50 Monobutyl acid orthophosphate 5 EXAMPLE XII A lacquer was prepared by dissolving the'following solid components in the solvent on an 80/20 solvent-tosolids weight basis:

Parts by weight Ethyl cellulose (46.8-48.5% ethoxyl, 22 centipoises) 100 Adrnex 710, epoxidized triglyceride of soya bean oil 50 RC-718, butanol-modified meat-formaldehyde resin 50 Dibutyl phthalate l Monobutyl acid orthophosphate EXAMPLE XIII A lacquer was prepared by dissolving the following solid components in the solvent on an 80/20 solvent-tosolids weight basis:

Parts by weight Cellulose acetate butyrate (26% butyral, 20.5%

acetyl, 2.5% hydroxyl, 900-1350 centipoises) 100 Admex 710, epoxidized triglyceride of soya bean oil RC-718, butanol-modified urea-formaldehyde resin 50 Dibutyl phthlate l0 Monobutyl acid orthophosphate 5 EXAMPLE XIV 3. EXAMPLE XV A lacquer was preparedby dissolving the following solid components in the solvent on an /20 solvent to solids weight basis: Parts by weight Ethyl cellulose 42.543.5% ethox' 22 cnfi;

poises) Admex 710, epoxidized triglyceride of soya bean 'oil 100 Uformite F-ZGO-E, butanol-modified urea-formaldehyde resin manufactured by Rohrn & Haas Company 40 Dibutyl phthalate 12.5 Monobutyl acid orthophosphatea 4 EXAMPLE XVI A lacquer was prepared by dissolving the following solid components in the solvent on an 80/20 solvent-tosolids weight basis: 7 I

' Parts by weight Cellulose acetate bu'tyrate (26% butyral, 2 0.5%

acetyl, 2.5% hydroxyl, 900-1350 centipoises) 100 Admex 710, epoxidized triglyceride of soya bean Oil Uformite F-200-E, butanol-rnodified urea-formaldehyde resin 100 Dibutyl phthalate 25 Monobutyl acid orthophosphate afleeee l0 EXAMPLE XVII solids weight basis:

weight 1,081) 100 formite F-200E, butanol-modified urea-formaldehyde resin 50 Dibutyl phthalate- 25 Monobutyl acid orthophosphate 5 The preparation of a variety of representative coating compositions of the present invention has been described and illustrated in the foregoing examples. Examples XVIH and XiX which follow, together with Tables 1 and 2, show the improved solvent and chemical resistance of an exemplary number of these new coating compositions.

EXAMPLE XVIII Several nitrocellulose-based coating compositions pre; pared in accordance with the present invention and several typical, otherwise comparable, commercially-available coating compositions were applied to unprimed wo'od panels by a suction-type spray gun a-t'roorn temperature. The coating compositions were flashed at room temperature (25-30 C.) for one-half hour and then force-dried at 80 C. for one hour. The thickness of each dry film was approximately 2 mils. Five drops of each of a variety of solvents and chemicals were applied to each of the coated panels four days after force drying of the coating composition. To prevent evaporation, the solvents and chemicals were covered with a watchglass for one hour after which the panels were washed with soap and water and wiped with a cloth wet with naphtha. The condition of the coating on the panels was then observed. Table 1 which follows contains a summary of the effect upon the coated panels or" the various solvents and chemicals. A key to the abbreviations used directly follows the table;

Table 1 APPEARANCE OF LACQUERS ON WOOD PANELS EXPOSURE TO VARIOUS CHEMICALS FOR ONE Ethyl SD-2B Chloro- HCHO Acetic Coating compositions acetate Acetone Methanol ethanol Ether form 0014 (36.8%) Phenol acid (85-88%) (99.7%)

Lacquer of Ex. I Tr Tr Tr S1 Lacquer of Ex. II. Tr 'Ir Tr S1 Hvy Lacquer oi Ex. III Tr Si Si Lacquer of Ex. IV Tr Tr N C Lacquer A" Hvy Hvy VHvy Mod S1 VSl VHvy VHvy NC Lacquer B Hvy Hvy Hvy Hvy S1 Tr Tr Si VHvy U-rF Varnish 4 VHvy Tr Coating compositions H1S04 HNOa (30%) NaOH (30%) Toluene HOl (37%) N H OH (20%) Htot 1 we er Lacquer of Ex. I LDis., OK MDis., K Lacquer of Ex. II Lacquer of Ex. TIi Lacquer of Ex. IV LDis., OK NC Lacquer A Sl Si MDis., OK NC Lacquer B MDis., bad LDis., bad MDis., OK U-F Varnish DDis., OK Tr MDiS., bad

Nora-Key to ratings:

=No evidence of attack.

Tr=Tracc attack. film protectiveness unimpaired. VSl=Very slight attack. illm protcctiveness unimpaired. Sl=Slight attack, film protectiveness unimpaired. Mod=Moderate attack, film protectiveness damaged. Hvy=Heavy attack, film destroyed.

VHvy=Very Heavy attack, film destroyed.

LDis= Light discoloration.

MDis=Mediurn discoloration.

DDis=Dark discoloration.

0K= ilm gloss and protcctiveness unimpaired. Bad=Fiim gloss and/or protectiveness damaged.

1 Hot water exposure was for 5 minutes at 190-205" F. I NC Lacquer is Duco" 15200, M alkyd-modified commercial nitrocellulose lacquer manufactured by E. I. duPont de Nemours & Co.

3 NC Lacquer "B" is a commercial straight nitrocellulose lacquer. U-F Varnish is Dulux Eli-5200, a commercial varnish manufactured by E. I. duPont de Nemours 6; Go.

EXAMPL X a substantial extent unattacked and unaficcted by the 501- The procedure of Example XVIII was repeated in convents and chemicals referred to in the tables. The connection With a num r f the new Coating compfislfions ventional cellulose derivative lacquer compositions, howand comparable representative commerciallyavmlable ever, are severely attacked by esters kctoncs alcohols compositions having cellulose derivative film-formers other Henol and acetic acid Whprea a conlm f than nitrocellulose. The effect of the various chemicals s em urea gm}- and solvents on the coatings was observed, as in Example alilehyde varmsh severely attacked by phenol mmc XVIII. Table 2 which follows contains a summary of the acid and hydrochlonc acld' As noted, above, the epoxidized material may be either results of these tests. A key to the abbreviations used 45 directly follows the table. epoxidized triglyceride of soya bean oil or epoxidizcd Table 2 APPEARANCE OF LACQUERS ON WOOD PANELS AFTER EXPOSURE TO VARIOUS CHEMICALS FOR ONE HOUR Ethyl Acetic HNOs H01 NaOH NHlOH Coating compositions acetate Acetone Methanol Phenol acid (30%) (37%) (28%) Lacquer of Example XI Si. Si. Mod. Mod. VJIvy. Dis, had Nil V.Hvy. Nil Lacquer oi Example XV Tr. Nil Nil Mod. Mod. H.Dis., bad Nil H.Dis., bad Nil Typcic a l conventional ethyl cellulose lacquer V.Hvy. V.Hvy. V.Hvy. V.Hvy. Hvy. Dis., OK Tr. Vfivy. Tr. Lacquer of Example XIII V.Sl. T1. Mod. Nil Evy. H.Dis., bad Nil M.Dis.. bad Tr. Lacquer of Example XVI Tr. Tr. Sl. Nil Mod. Dis., bad Nil H.Dis., bad Nil Typiclal conve nional cellulose acetate butyr- Hvy. Hvy. Hvy. V.Hvy. V.Hvy. V.Hvy. V.Hvy. L.Dis., OK Tr.

ate acquer NorE: Key to ratings:

N ll=No evidence of attack. Tr.=Trace attack, film rotectiveness unimpaired. V.S1.=Very slight attac film protcctiveness unimpaired. Sl.=Slight attack, film protectiveness unimpaired. Mod.=Moderate attack, film protectiveness damaged. Hvy.=Heavy attack, film destroyed. V.Hvy.=Very Heavy attack, film destroyed. L.Dls.=Light discoloration. M.Dis. =Med1um discoloration. D.Dis.=Dark discoloration. OK=Filrn gloss and protectiveness unimpaired. Bad=Filrn gloss and/or protectiveness damaged. 1 Ethyl cellulose (ethoxyl content 46.848.5%, viscosity 22 cps.)-100 parts by weight; ester gum-100 parts by weight; raw castor oilparts by weight. dispersed on an 80/20 solventto-solids weight basis in the solvent system of Examples XIII-XXIII, above.

1 Cellulose acetate butyrate (26% butyral, 20.5% acetyl, 2.5% hydroxyl, viscosity 900-1350 cps.)100 parts by weight; "Santalite MHP" aryl sulfonamide-formaldehyde resin manufactured by Monsanto Chemical Co.- parts by weight; dibutyi phthalate-50 parts by weight; dispersed on an /20 solvcnt-to-solids weight basis in the solvent system of Examples XIII-XXIII, above.

It will be readily apparent from Tables 1 and 2 that acetylatcd triglyceride of castor oil, which are obtained the coating compositions of the present invention are to as the reaction products of hydrogen peroxide orperacetic acid with unsaturated fatty acid esters and the oils, as disclosed in vol. 67, I. Am. Chem. Soc. (1945), pp. 412-414.

The epoxidized material may be cured "with aureaformaldehyde, melamine-formaldehyde, or ben zoguanamine-formaldehyde resin. The resins which are used are prepared by the con'densation-of..urea.or thetriazine .with

/ bined form from about one-half to about one'molecule of the alcohol and' about 'Z rntiIecuIes of formaldehyde for each molecule of -urea, melamine, flr-benzog-uanamine. In some cases, resins having as much as 1.5 molecules of the alcohol per molecule of urea," niel'aminefor'benzoguanamine or the triazine may be used.

indicated above, 'the present inventionr-relates to improved cellulose derivative coating compositions, and theanew compositions Twill therefore contain, in addition 1o: thezioreg'oing components, an'organicesolvent soluble cellulose derivative film-former such :as :nitrocellulose, e'thyl cellulose, celluloseacetate, cellulose acetate butyrate, 'icellulose:acetate.1propionate,-:'benzykcellulose, orfthelike. Especially good results have been obtainedwithinitrocelludoses-based 1 compositions, and these representthe. much apreferred embodiment .of the invention. However, the :invention isoperative andadvantageous in connection with uthe 'other.organic-solvent solubleicellulosederivativefilmsformers as is illustrated by the foregoing examples. It is within the scope of the inventiomto-prepare novelicoating compositions of the type described having film-forming -tcomponents containingltwo or'more different cellulose rderivatives, ora cellulose derivativemixedwithportions rof" a 'non-cellulosic film-former; such as amalkydresin or ithe like.

With nitrocellulose lacquers, the nitrocellulose used stwilligenerally contain-from about 10.7% about 12.2% rsnitrogen and will have ;..a viscosity betweennabout-Ms i'SECOHd-T'Zmd 100 seconds-as ideterminedby standard methfi'odstASTM met-hod D301-=50') Ty pe HB --l'4-..'E.-nitro- "icellulose-zmanufacturedi byzEs I. du:'P0nt de Nernours-and Company, Inc. illustrated in a number of the examples 'is a 'typi'cal suitable cornmer'ciallyravailable nitrocellulose.

' With ethyl cellnlose lacquers, any conventional "lacquer grade ethyl cellulose may"be=used,'such as ethyl cellulose products having an e't-hoxyl content between about 42 and 50% and a viscosityofiabout #Zildcenti- 'poises. Siniilarly, any "commonly "used lacquer grade cellulose acetate butyratema'ybe used as" the film fo'rmer, "including, 'for example, such, prtiduetsfhavin'gfla .viscosity of from about 80-360 centipoisesan'dester group contents in the following :general ranges: butynal 17-48% acetyl 6-29.5%,...hydroxyl 0.7-.2.5%.

10 Thecoating composition may frequently also contain a plasticizer for the cellulose derivative which may be 'any conventional plasticizer frequently used for these materials, such as 'dibutylphthalate,tricresylphosphate, di(2-ethyl hexyl) phthalate, dibutyl sebacate, castor oil,

modified castor oils, camphon-onthe-like. However, in

cellulose derivative. In ;such-case s, suflicient amounts 1 will be added to provide for plasticization of the cellulose derivative"in"'addition"to enhancement -of--the-solvent 'and chemical resistance of the lacquer.

To increase the rate of cure of the epoxidized material with the urea-,-melamine-, or benzoguanamine-formalde- "hyde resin, asuitable catalyst may be used. (Because of the tendency ofzn'itrocellulose tofdegradei in' the, presence of basic substances, neutral oracidic catalysts, such 38 citric acid'or monomethyl,imonoethyl, monobutyl, or

other mono-lower alkyl acid' orthophosphate,.are preierredfor this: purpose with the,rnitrocellulose.lacquers.

With the other cellulose:derivatives,:anysuitable catalyst may be used.

-Inadditionto the foregoing components, nitrocellulose lacquers prepared-in accordance withthe present-invention may containsa cross-linkingagentzfor the nitrocellulose, such-as titanium ethyl-acetoacetate, inwhich case an acid gel inhibitor. :is also -used,-;such-*as pyromellitic :acid.

Other cross-linking agentssfor the nitrocellulose-are 0perable as, for example, thosedescribed in U.S. Patents 2,680,108 and 2,686,133. :The coating compositions of the present invention may ialso-contain :any of awide variety of other conventional compounding ingredients 'for such compositions including, tor-example, dyes,jpig- :m'ents, stabilizers,- anti-set'tlingagents, dispersion aids, and

the like.

The coating compositions of the present "invention have all the desirable properties of conventional cellulose derivative lacquers coupled with superior resistance 'to attack by such solvents and chemicals asalcohols, esters, 'ketones, aldehydes, aromatic and aliphatic hydrocarbons, chlorinated hydrocarbons, organic and mineral acids, andalkalies. IThe compositions 'dry tack freejiin air with. good physicalproperties-and require a low bake curing cycle only to eifect thechemical resistance. The

. coatin compositions-alsolhave excellent physical properties including, for example,color stability on exposurerto ultra-violet light andadhesionto-wood, steel andcalumi- .num. :The coatings formed with these compositions-are iquite flexible," extremely hard, andhave' excellent impact resistance when comparedwitli many 'commercially available lacquer compositions. :A:compar iso'n of 'so'mecof the physical properties of films iormed from typical coatingcompositions-prepared in accordance with the present inventionwith-films formed frorn conventional f prior art lacquers Wilfbefound in Table '3.

L'Table 3 PHYSICALTPROPE'RTIES ON' UNPRIMED'PANEIJS Adhesion i20 nnpact= Flexibility- EPencll (Percent) (55 mandrel) hardness l Qoatingcomposttion V I Eagle Steel Aluml- Steel Aluml Steel Aluml quois'e" num num num Lacquer prepared according to U.S. Military Speclfi- O 0 F F F F GE.

cation MIL-L-19537 (Aen) of June 7, 1956, as amended March 4, 1957. Lacquer prepared according to U.S. Military Specl- 0 0 F F F F 3B. fioatlon MIL-L-l9538 (AerJ of June 7, 1956, 8S amended March 4, 1957.

See footnotes at end of table.

Table 3-C0ntinued PHYSICAL PROPERTIES ON UNPRIMED PANELS Adhesion 1 20" impact 1 Flcribility 3 Pencil (Percent) M mandrel) hardness 4 Coating composition E lagulre Steel Alurnl- Steel Aluml- Steel Alumlquoise" num num nun:

Lacquer prepared according to Example XII 100 86 0.1:. 0.K. 0.K. O.K. M. Typical conventional ethyl cellulose lacquer 100 0 F F O.K. 0.K. HB. Lacquer prepared according to Example XIII 100 100 O.K. O.K. O.K. 0.11. HB. Typlcal conventional cellulose acetate butyrate lac- 0 0 0.K. 0. 0.K. 0.15. GB.

quer.

N urn-Key to ratings: O.K.=Coating did not fail. F=Coatlng failed.

1 Adhesion: "Scotch Tape" testdescrlbed in 11.8. Patent 2,751,316 (column 2, llnm 58-64) 1 Impact: DuPont-Parlin type impact testerdescribed in Gardner and Sward, "Physical and Chemical Examination or Paints,

varnishes, Lacquers, and Colors (th ed.), p.

173. 3 Flexibility: ls" runndlel test-described in Gardner and Sward, "Physical and Chemical Examination or Paints, varnishes,

Lacquers, and Colors (10th ed.). p. 171.

4 Pencil Hardness: 05 Die. Fcd'n. P

6 Same as lacquer "C". Table 2.

6 Same as lacquer D, Table 2.

As noted above, the catalyst (where used) which promotes the curing of the epoxidized material is not compounded with the other components of the lacquer at the time of manufacture. It is added later by the consumer, for example, usually about l-24 hours before the lacquer is used; the shelf-life of the thus catalyzed lacquers depends on the specific formulation and storage conditions and may be as high as two months or more.

After the composition is applied to the surface which is to be coated, the epoxidizcd material is cured by a. low-bake curing cycle at a temperature anywhere in the range of about 50 to 125 C. for a period of about A to 8 hours.

Based upon a solids composition containing 100 parts by weight of the cellulose derivative, the epoxidized material will be used in an amount of about 50 to 100 parts by weight whereas the urea-formaldehyde, melamineformaldehyde, or benzoguanamine formaldehyde resinous curing agent will be used in an amount of about 8 to 50 parts by weight depending upon the amount of epoxidizcd material present and the specific properties desired in the coating composition end product. When a catalyst is used to promote the curing of the epoxidizcd material, the catalyst will be present in amounts of about 3 to parts by weight, based on 100 parts by Weight of the cellulose derivative. As noted above, the cellulose derivative may or may not be plasticized. There may thus be present anywhere from O to about 80 parts of cellulose derivative, per 100 parts by weight of plasticizer depending on the type and grade of cellulose derivative employed and the properties desired in the finished product. Coating compositions which are intended to be used on rigid substrates, such as metal surfaces, will contain lesser amounts of plasticizer, and in some cases, no plasticizer at all. On the other hand, coating compositions which are to be applied to flexible substrates, such as leather and the like, will often be highly plasticized in order to impart the necessary flexibility to the coating. The amount of plasticizer to be used in any particular instance may thus vary widely within the indicated range depending upon the nature, properties, and function of the surface to be coated.

Where a cross-linking agent for the nitrocellulose and an acid gel inhibitor are used (in the case of nitrocellulose lacquers), these materials will generally be present 6: V Prodn. Clubs 28 N0. 374, March 1956, pp. 232-237, W. T. Smith.

in amounts of about 1.5-8.0 and 0.1-1l.5 parts by weight, respectively, per 100 parts of nitrocellulose.

As used in this specification, the term epoxide value refers to gram equivalents of epoxide per 100 grams of epoxidized material.

This application is a continuation-in-part of our prior copending application Serial Number 720,091, filed March 10, 1958, now abandoned.

Having thus described our novel coating compositions, it will be readily apparent to those skilled in the art that many changes and modifications may be made in the particular procedures and compositions described without departing from the spirit of the invention. We therefore intend to be limited only by the following claims.

We claim:

1. A coating composition comprising an organic solvent solution of (a) a cellulose derivative film-former, (b) an epoxy composition from the group consisting of epoxidized triglyceride of soya bean oil and epoxidizcd acetylated triglyceride of castor oil, and (c) a resinous curing agent for the epoxy composition selected from the group consisting of the alkanol-modified urea-formaldehyde, melamincformaldehyde and benzoguanamincformaldehyde resins, the ratio of (b) to (a) being about 50-100/100, and the ratio of (c) to (a) being about 8-50/ 100.

2. A composition as inclairn 1 which contains up to parts by weight of a plasticizer for the cellulose derivative per parts of the latter.

3. A composition as in claim derivative is nitrocellulose.

4. A composition as in claim 2 wherein the cellulose derivative is ethyl cellulose.

5. A composition as in claim 2 wherein the cellulose derivative is cellulose acetate butyrate.

2 wherein the cellulose References Cited in the file of this patent UNITED STATES PATENTS 2,732,367 Shokal Ian. 24, 1956 2,754,285 Petropoulos July 10, 1956 2,843,560 Mika July 15, 1958 FOREIGN PATENTS 141,457 Switzerland Oct. 1, 1930 

1. A COATING COMPOSITION COMPRISING AN ORGANIC SOLVENT SOLUTION OF (A) A CELLULOSE DERIVATIVE FILM-FORMER, (B) AN EPOXY COMPOSITION FROM THE GROUP CONSISTING OF EPOXIDIZED TRIGLYCERIDE OF SOYA BEAN OIL AND EPOXIDIZED ACETYLATED TRIGLYCERIDE OF CASTOR OIL, AND (C) A RESIONOUS CURING AGENT FOR THE EPOXY COMPOSITION SELECTED FROM THE GROUP CONSISTING OF THE ALKANOL-MODIFIED UREA-FORMALDEHYDE, MELAMINE- FORMALDEHYDE AND BENZOGUANAMINEFORMALDEHYDE RESIN, THE RATIO OF (B) TO (A) BEING ABOUT 50-100/100, AND THE RATIO OF (C) TO (A) BEING ABOUT 8-50/100. 